docs: def tag_report_cb(llrp_msg):
      """Function to run each time the reader reports seeing tags."""
      global numtags
      tags = llrp_msg.msgdict['RO_ACCESS_REPORT']['TagReportData']
      if len(tags):
          logger.info('saw tag(s): %s', pprint.pformat(tags))
          for tag in tags:
              numtags += tag['TagSeenCount'][0]
      else:
          logger.info('no tags seen')
          return